Pressure-limiting gauge



Aug. 4, 1925.

' J'. D.F|RTLEA PRESSURE LIMITLLNG GAUGE FildV Feb. 23. 1924 mm. um m AN MN Q LmNAA/////////////./,//// V :llllII W/V//J/ Mm ZUZ'ZIZQSS 'Patented Aug. 4, 1925.

UNITED STATES 1,548,206 PATENT oFricE.

. JOE DAVIS PIRTLE, OF CHICAGO, ILLINOIS.

PRESSURE-LIMIT'ING GAUGE.

Application yfiled February 23, 1924. Serial No. 694,461.

ATo all whom t may concern: Y

.Be it known that I, JOE'DAVIS PIRTLE, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have iiiventedvcertain new and useful Improvements in Pressure-Limiting Gauges, of which the following is a' specifi-v cation. ,A

This" invention relates to a gauge to be introduced into aconduit through which a fluid medium is supplied underpressure, and Which will act to arrest the delivery of the fiuid medium as soon as the latter attains a predetermined pressure in the space being charged.v

Theobject of the invention is to' 'provide a gauge of this general class with'an improv-ed operative principle, the underlying feature of which consists in having the piston,` which controls the valve that cuts off the supply of fluid, arranged not only' to move in opposition to a weighing means in response to pressure accumulated by the liuid, as in. devices heretofore.employed for vary the pressure at which the valve is veral -features ofv the present invention, `and ,this purpose, butto execute this movement at first and lfor Aa -substantialportion of the throw of the piston', independently of the vvalve which the -pis'toncontrolsso that the` weighing operation may be better accomplished, and the'valv-e will be picked up and moved to its ,seat by the latterpart of the -movement of the piston. Another feature 'consists in havingthe weighing element,

preferably a compression spring, substantially constant in resistance whichdt opposes to the pressure-actuated piston, and to closed by shifting thebmeans through which the piston-picks up the valve. Other features relate to details of construction wherebythe several underlying features mayl be advantageously realized.

' In 'the accompanying drawing-1` Figure 1 is a longitudinal section of a pressure-limiting gauge embodying the sevdesigned for use in controlling the inflation of pneumatic tires.

designed for establishing air-tight connection with a stein, such'as A, as, for instance, by providing the nozzle Awith an annular packing 2 fitting vthe stem A and a sleeve 3 confining the packing to the nozzle. -Such nozzle also preferably equipped 'with an unseating stud 4 protruding from its end in v position to engage the valve sterli 5 usually found vvithin an inflatingstem; said stud being preferably provided by threading into the. end of the nozzle l 'a short nipple having its end transversely apertured as at 6 to permit escape of fluid loeinf-.rcharged,ll while the stud is resting upon the stem ofI the valve."

vNozzle 1 is carried by a shell 7, as for in` stance, by threading it to the shell at 8, and this shell .also carriesv a supply nipple -9 through which fiuid under pressure may-be deliver-ed to the shell; also a valve seat 10 surrounding an escape passage 11 andadapted to receive a valve 12 for arresting the flow of fluid through said escape passage. is a, cylinder 13 in which works a valve-controlling pisfon'14'that is subject t0 pressure Likewise mounted upon the shell 7 offluid beyond the valve 12, and communication-is established byl a duct 15, between the pressure -side of piston 14 andthe duct 16 in the nozzle, 1, so that pressure accumulating in a. space supplied by said nozzle will react through the ducts 16 and 15 `upon the piston 14 and ytend to move theF-latter in the cylinder 13. Opposing movement ofpiston 14 under such pressure is a weighing means, preferably in t'lieform of aspiral spring or springs, located between the piston 14 and a fined abutment 17, Whichlatter -is con- "l veniently provided by deflecting'inwardly one or more tongues struck from the metal of the cylinder 13. This weighing means preferably comprises a main spiralspring 18 for -weighing heavier pressures devel- "'.oped `in the space being charged, and an auxiliary spring 19 for weighing lighter pressures; the auxiliary spring being preferably constructed with a capacity thatl will beexhausted before the main spring begins to compress, and the load of the former spring being imposed upon the latter spring through the medium of a traveling parti tion 20 which receives the piston 14 afterl the Aauxiliary spring is compressed, and which'is formed with a chamber or recess 21v that admits said auxiliary spring 19 when in its compressed state.

The described weighing 4means is de- .signedl primarily to adapt the' gauge to serve for either the so-called ballon tires,

lin which relatively low pressures are maintained, 0r for hard tires, in which much higher pressures are required.

In order that the piston, 14 may pick up the valve 12 and move it in the direction of closing only asthe piston approaches the limit of its movement under pressure to be accumulated, said valve. carries upon 'its rod 22 a stop or shoulder 23 which is in the path of but normally spaced away from the outer end of a stem 24 carried by 'the piston 14, and Which is preferablv of tubular form and concentric with the rod 22 of the valve. And in order that the stop 23 may be given diii'erent positions relatively-to the rod 22, and thereby determine the degree of compression in the Weighing means 18, 19, Which musttake place, and therefore the degree of pressure which mss' I have accumulated-before the valve is closed.,

said stop 23 is connected with the rod 22 through means of a threaded core or bushing 25 adapted'to be rotated by the knurled head 26'; the stop 23 being held againstI rotation by a stud 27'Working in a slot 28 of the cylinder' 13, and being caused to move in the direction of the axis of the valve and piston by the rotation of said knurled head.`

F or convenience in producing the threaded `piece 23, constituting the stop on the piston rod 22, the bore in said piece Which receives the adjusting'bushing25 extends entirely through the piece and is closed at the inner end by a Washer 23a that provides the necessary abutment. for the tubular stem 24 of the piston 14. [Stud 27 and the Walls of the slot 28 Witlrwhich'it cooperates, bearing suitable ygraduations, afford .convenient means for Calibrating the position of the stop '23, and, therefore, vthe pressure that will be permitted to accumulate before the Y valve 12 shuts off the How." Bushing- 25, be-

ing free to rotate' upon` the valve rod 22, is made to transmit movementof the stop 23 by engaging beneath the head 29 upon the valvevrod. Bushing 25, and stop 23 Which it carries, Will be normally returned `from valve-closing movement and held inwardly by means ot a spring 30.9Sorne4 means ofyieldingly holding the check valve from its seat until the weighing movement is about completed'is desirable in order to leave a reespace for the flovv of air and to avoid premature closing of the valve under the pressure that is being measured. The frictional lit between the bushing 25 and the valve rod 22 may be suilicient .to hold the valve open, notwithstanding friction of the piston stem uponthe rod, While the load is accumulating, or the users thumb or hand may be so held over the valve rod head 29 as to prevent premature seating o1 the valve under frictional'iniuence of the piston stem 24, in which ease, `the forcible movement ofthe heads 2 6 and 29, as the limit of pressure is approached, will ap-A prize the user of the completion of 'the charging operation.

In constructing a device embodying the operative principles above described, the -noz'zle 1 and the cylinder 13 are preferably formed separately. from the shell 7; the chamber 3.1 lin which the valve 12 operates will be closed by a removable plug 32 to permit removal of the valve from its rod; and the outer end of the cylinder Will be closed by the end cap 33. But these and other details of the embodiment selected for purposes of illustration may obviously be changed Without departing from the spirit of the invention.

F rom the foregoing description it will be seen that the main spring 18 'and auxih'ary spring 19 are arranged to act iu tandem against the piston 14, the thrust of the -piston vbeing imparted through one:

springt-o the other, and, preferably, the ini- -tial resistance'of the main spring18 Will be such as to develop no Weighing movement 'of the compressible spring is much better lthan in devices where the pistonis connected to the valve without lost motion, and. closing movement. of the valve `immediately follows and results from the initial movement of the'piston, and Where, as a consequence, the Weighing spring must be lengthenedor shortened and its initial compression! changed lin order to predetermine the pressure of fluid accumulation at which thel gauge will act.

1. In a vpressure limiting fluid supply gauge.y a valve movable to control the flow ot' fiuid, a pressure* Weighing means, and a? can ,valve actuating piston oppositely acted' upon b v the pressure to be gauged and b v said weighing' means; said piston 'moving independently of its controlled valve in Weighing the pressure to be accumulated, andv picking up the valvevto initiate closing movement as the end of the Weighing movement is approached.

2. In a pressure limiting 4fluid sup ly gauge,'a valve movable to control the ow of fluid, a pressure Weighing means, and a' los Astop through which the valve is moved, vreceiving movement from the piston only after the latter has performed a Weighing movement.

4. In a pressure limiting lfluidI supply gauge, a valve movable to control the flow of fluid, a pressure Weighing means, a piston oppositely acted upon by the pressure to be gauged and by said weighing means, anda 4 stop through Which the valve is moved, re-` ceiving movement from the piston after the latter has performed a Weighing movement lsaid stop being adjustable relatively tothe i for controlling` the `plurality of springs of I for controlling the flow of valvel to vary the extent of Weighing movement of the piston that occurs before movement is transmitted to the valve.

5. In a pressure limiting gauge, a valve adapted to control the flowof Huid, a piston forv actuating said valve, subjected to pressure of the medium to be controlled, and a Weighing means acting upon said piston. in opposition to said pressure; said Weighing means comprisingv main* and auxiliary springs developing separate Weighing effects. 6. In a pressure limiting gauge, a valve flow of pressure medium, a piston adapted toimpart movementto said valve, and a Weighing means comprising a acting in tandem against said piston in opposition t0 the pressure medium.

7. In .a pressure limiting gauge, a v alve pressure m'edium, a piston .adapted to impart movement to said valve, and a Weighing means comprising a plurality of springs of diderent capacity acting in tandem against said piston in opposition to the pressure medium; one of said vsprings having an initial resistance approximately equal to. the ullweighing capacity of another "of saidsprings. p

8. In a pressure limiting gauge, a valve for controlling flow of. pressure medium, a piston subjected in one direction to the'vaction of said pressure medium, and a Weighing means opposing movement of the piston by said pressure medium; said weighing means comprising a main spring and an auxiliary spring acting on said piston, theorie through the other,v and a partition inserted between said springs through Whichthrust is imparted from one'spring to theother.

9. In a pressure limiting gauge, la valve different capacity j vfor controlling flow of pressure medium, a piston subjected in one direction to the ac-. tion of said pressure medium, and a Weighing means opposing movement of the piston by said pressure medium; lsaid Weighing means comprising a main spring and an auxiliary4 spring-acting on said piston, vthe one through the other, and a partition inserted between said springs throughl which thrust is imparted 'from one springto the other;

said partition beingprovided With a recess adapted toreceive the auxiliary spring When compressed.

10. In a pressure limiting gauge, a' valve for controlling flow of pressure medium, a'

piston'subjected in one direction to the ac-v tionv of said -pressure medium, and a Weighing 'means opposing movement of the piston by said pressure medium; said Weighingv means comprising a main spring and an auxiliary spring acting on said piston, the one-through the other, and a partition inserted between said springs through which thrust is imparted from one spring .to the 'otherg the auxiliary spring being interposed between the main spring and the piston.

11. In a pressure, limitinggauge, a valve for controlling flow of pressure medium, a piston subjected in one direction to the action ot' said pressure medium, and a Weighing means opposing movement 'of the piston by said pressure medium; said Weighing means comprising a main spring and anA auxiliary spring acting on said piston, the

is compressed.

12.` I n a pressure-limiting gauge, a valve adapted to control the flow o pressure medium, a rod. through Which said valve is controlled, a stop through which the valve 'rod is moved, a piston acted upon in one direc- `tion by the pressure medium, a Weighingl means ieldingly resisting movement of the piston y the pressure medium, and a piston stem adapted to engage said stop and' iinpartmovement t0 the valve after Weighing movement of the piston.

13..-In a pressure limiting gauge, a valve -adapted to control the flo'vv of pressure medium, a rod through Which said valve is coitrolled, a st op through Which the valve vrod ismoved, a pistonacted upon in one l direction by the pressure medium, a Weighing means yieldingly resisting movement of the piston by the pressure medium, and a piston stem adapted to engage said stop and impart-movement to the valve after Weighing movement of the piston; said stop being ment of lthe piston and transmit thrust to the main spring after the auxiliary spring ing relatively to the other, whereby it in1- parts adjustment to the stop relatively to 4the rod, a Weighing means, and a piston acted upon in one direction by thepressure "medium and in the other direction by the WeiO'hinOf means' said iston bein0` ada ted D C5 7 ZD to impart movement to said stop.

l5. In a pressure limiting gauge, a housing, avalve for controlling the fioiv of pressure medium, a piston acted upon by the pressure medium having a Weighing means resiliently opposing'its movement, and va' valve rod adapted to receive movement from the piston after the latter has performed a Weighing movement; said valve rod extending beyondsaid housing and serving to disclose movement of the valve.

16. In apressure limiting gauge, a housing, a valve adapted to control the f iow of pressure medium,A having. a rod extending through said housing, a piston adapted to be vacted upon in one direction by pressure medium and lhaving va lresilient `Weighing means acting upon it in the opposite direcl tion', a steml extending from said piston in the direction of 4said vvalve'rod, a stop on said valve rod in the path of the piston stem, an adjusting sleeve ,adjustably'supporting said stop upon said valve rod, and a turning head in said sleeve beyond the confines of the housing.

17. In a pressure limiting gauge, a housing, a valve adapted .to control the iowof pressure medium, having a rod extending through said housing, a piston adapted to be acted upon in on@ direction by pressure medium and having a resilient Weighing means acting upon it in the opposite directioina stem extending from said piston in the direction of said valve rod, a stop en said valve rod in the path of the piston stem, an adjusting sleeve adj ustably` supporting said stop upon said valve rod, and a turning head in said sleeve beyond the confines of the housing; said valve rod extending through and having a head overlapping the sleeve head.

18. In a pressure limiting gauge, a housing, a valve for controlling the iioiv ofvpresf sure medium, having a rod extending longi-4 tudinally of the housing, a piston adapted .to b e acted upon in one direction by the pressure medium and having a resilient weighing means 'acting upon it in opposition to said pressure medium, a stem extending from said piston in the direction of the valve rod a stop mounted on said valve rod -in the path 0f said stem', and a spring acting upon said stop to return it lto normal position when released by the piston stem; said stop and piston stem .being related to permit the piston to execute Weighing movement before encountering the stop. l

` Signed at Chicago, Illinois, this 20th day of February, 1924.

JOE DAVIS PIRILE. 

